ES2327299T3 - PROCEDURE AND EXTENSION SYSTEM OF SEQUENCE NUMBERING RANGE FOR SELECTIVE TRANSMISSION REPETITION PROTOCOLS. - Google Patents

Abstract

A method for transmitting data between a transmitter (50) and a receiver (52) using a frame (70) having a sequence number (72) and a retransmission indicator (74) comprising the steps of: a) transmitting the frame (70) a first time with said retransmission indicator (74) set to false and the sequence number (72) comprising a first number of bits and set to the least significant bits of an index code comprising a second number of bits, greater in number than the first number, b) increase a value of said index code for the use of a following frame; and c) retransmitting the frame (70) a second time with said indicator (74) set to true if a negative acknowledgment message containing said frame index code (70) is received on said transmitter (50).

Description

Procedure and system for expanding the range of sequence numbering for transmission repeat protocols selective

Background of the invention I. Field of the invention

The present invention relates to a procedure and system to transmit digital data. The present  invention is suitable for expanding the numbering range of sequence that can be applied to repeat protocols of selective transmission

II. Description of the related technique

Figure 1 is a block diagram of a Personal communication system configured according to the use of the IS-95 air interface standard. The standard IS-95, and its derivatives such as IS-95-A, IS-99 and IS-707, IS-657 and ANSI J-STD-008, etc. (to those who do collectively referenced in this document as the IS-95 standards), define an interface for implement a digital personal communication system that uses split access signal processing techniques of code (CDMA). Also, a personal communication system configured substantially according to the use of IS-95 It is described in US Patent 5,103,459 entitled "System and Method for Generating Signal Waveforms in a CDMA Personal communication System "transferred to the assignee of the present invention

As usual in most systems personal communication, the IS-95 allows provide mobile phone service to a set of terminals wireless (usually cell phones) that use a set of 12 base stations coupled to public telephone network 18 switched by a transmitter controller 14 (BSC) and a center 16 mobile switching (MSC). During a phone call, a wireless terminal 10 interconnects with one or more stations 12 base using CDMA modulated radio frequency (RF) signals. Be refers to the RF signal transmitted from station 12 base to the wireless terminal 10 as the direct link, and it is done reference to the RF signal transmitted from terminal 10 Wireless to base station 12 as the reverse link.

Conforms to IS-99 standards and IS-707 (referred to in continued in this document simply as IS-707), a communications system compatible with IS-95 can also provide services of data communications Data communications services allow digital data to be exchanged using receiver 10 and the RF interface on one or more transmitters 12. Examples of the type of digital data normally transmitted using the standard IS-707 includes computer files and mail electronic.

According to both the IS-95 standard such as IS-707, the data exchanged between a wireless terminal 10 and a base station 12 are processed in frames To increase the likelihood of a frame being transmitted successfully during a data transmission, the IS-707 uses a radio link protocol (RLP) to track the frames transmitted successfully, and to perform frame retransmission when a frame has not been Successfully transmitted. The retransmission that takes place up to three (3) times it is of type IS-707, and it is the responsibility of the top layer protocols carry out additional stages to ensure that the frame is transmitted with success.

In order to track those frames that have been transmitted successfully, the IS-707 requests that a number of eight bit sequence in each transmitted frame. The number of sequence is increased for each frame from 0 to 256 and then it Reset back to zero. A plot transmitted without success is detects when a frame with a sequence number is received messy, or an error is detected using sum information CRC check or other error detection procedures. Once a unsuccessfully transmitted frame is detected, the system Receiver transmits a negative acknowledgment message (NAK) to the transmission system that includes the sequence number of the plot that has not been received. The transmission system retransmits then the frame including the sequence number as transmitted originally. If the retransmitted frame is not received successfully, it will be sends a second negative acknowledgment message to the system transmission. The transmission system responds normally notifying the failed transmission to the control application or layer Network

According to IS-95A and IS-707, frames are transmitted once every 20 milliseconds (ms). Therefore, an eight bit sequence number you can track 256 frames transmitted in a five (5) second interval. Normally, five seconds is sufficient to allow a frame transmission to be detected failed, and a retransmission is made, and therefore a number of eight bit sequence provides enough time for the frame retransmission Therefore, retransmitted frames can uniquely identify without the ambiguity caused by a "cyclic reset" sequence by which the number is repeated of eight bit sequence.

However, since the original development of IS-95A and IS-707, have been proposed and developed protocols and standards that allow transmitting data at higher transmission rates. Normally, these new protocols and standards use the same frame structure as IS-95A and IS-707 in order to maintain as much compatibility as possible with the systems and existing standards. However, although it is desirable to maintain compatibility with existing standards and systems, the use of the same type of frame within these protocols and standards higher transmission rate, substantially increases the number of frames that are transmitted over a period of time dice. For example, if the transmission rate is increased multiplying it by four, the time required to transmit 256 frames are reduced to 1.25 seconds, instead of the five seconds that were previously required. A time period of 1.25 seconds is usually enough to allow a frame transmission failed, and a retransmission is attempted, before that the eight bit sequence number be repeated. Therefore the use of an eight bit sequence number is insufficient to allow unique identification frames over the period of time necessary to perform the desired retransmission sequence.

Although the number of bits in the number of sequence can be increased, such an increase would alter substantially the frame format and therefore would breach the objective of maintaining substantial compatibility with systems and existing standards. Therefore, the present invention is focused on a procedure and apparatus to expand the range of sequence numbers, without modifying the number of bits used for the Sequence number.

Additional attention is drawn to the US-A-4 617 657, which gives know that in a packet data transmission system, acknowledges receipt of information packets received correctly cascading their sequence numbers in packets of information that are being transmitted. The field of control of each packet of information includes a bit that indicates whether There is a receipt acknowledged cascading or not. The acknowledgments they can also be transmitted separately in packets of control that have no information field. Each acknowledgment it consists not only of the sequence number of a package of information received correctly, but also the status of acknowledgment of a plurality of information packets above, so you can acknowledge receipt of these so Negative if necessary. Sequence numbers can have one Any of three different sizes, for effective transmission of the sequence numbers on transmission links of transmission speed and length (and therefore delay) arbitrary The size of the sequence number that is used over any particular transmission link is determined according to the link configuration that depends on the transmission speed and the round trip delay of the link.

Summary of the invention

According to the present invention, a method for transmitting data, according to claim 1, a transmitter, according to claim 6, and a receiver, according to the claim 7. The embodiments of the present invention are claim in the dependent claims.

According to an example of the invention, it is provided a procedure to transmit data between a transmitter and a receiver using a frame that has sequence numbers that It comprises the steps of: a) transmitting the plot a first time with one retransmitted bit set to false and the sequence number adjusted to a part of a long sequence number; b) increase said long sequence number; and b) retransmit the frame with said retransmitted bit set to true when a negative acknowledgment message containing such long number of frame sequence.

According to another example of the invention, provides a procedure to transmit a set of frames of data that has eight bit sequence numbers comprising the steps of: a) adjusting a field of type to newly transmitted when the data frame is transmitted for the first time; b) adjust said type field to retransmitted when the data frame is is broadcasting; and c) transmit the data frame.

According to a further example of the invention, provides a system to transmit data through frames, comprising: a transmission system to transmit frames newly transmitted with a field type set to newly transmitted and a sequence number, to maintain an index L_V (S) that is increased once after transmitting each newly transmitted frame, and for transmitting retransmitted frames in reply to NAK messages; and a reception system to generate said NAK messages when said newly transmitted frames are receive messy, to maintain a list of NAK to perform track frames not received, and to reorder frames Retransmitted

An example of the invention also provides a transmitter for transmitting digital data, comprising the transmitter: a control circuit to generate, for fields of individual data, respective sequence codes, comprising each a first number of bits deducted from an index code which comprises a second number of bits greater in number than the first number; a transmission circuit to transmit together each respective data field and sequence codes as a data frame encoded in a carrier; and a circuit of reception, to receive and decode a data frame encoded, which comprises an index code and a no code acknowledgment of receipt, and in which the control circuit is arranged to identify from the decoded index code a sequence code and a respective data field for the retransmission as a data frame encoded by the circuit transmission.

An example of the invention further provides a receiver to receive digital data, the receiver comprising: a reception circuit to receive and decode a frame of encoded data that contains a data field and a code of associated sequence comprising a first number of bits; a control circuit to determine an index code from of the received sequence code, index code comprising a second number of bits greater in number than the first number, for compare the determined index code with index codes developed for respective sequence codes of frames of data received previously to identify the wrong reception of a received data frame, and to generate an index code for transmission with a non-acknowledgment code when detects an error in reception; and a transmitter to transmit jointly the index code and the acknowledgment code as a data frame encoded in a carrier.

The present invention is focused on provide a procedure and apparatus to expand the range of sequence numbering for a repeat protocol of selective transmission According to an embodiment of the invention, the data frames are transmitted including a sequence number of eight bits and a one bit retransmission indicator. The indicator One bit retransmission indicates whether the frame has just been transmitted or retransmit due to a failed first transmission. The transmission and reception systems each maintain a number of twelve-bit sequence referred to as "long sequence number "consisting of the sequence number of eight bits transmitted with each frame and an extension of four bits The long sequence number is transmitted within the control frames and the eight bit sequence number is transmitted within the data frames.

Brief description of the drawings

The characteristics, objects and advantages of the present invention will become more apparent from the description  detailed set forth below when taken in conjunction with the drawings in which similar reference characters the fully identify correspondingly and in which:

Figure 1 is a block diagram of a personal communication system;

Figure 2 is a schematic diagram of a transmitter and receiver;

Figure 3 is a diagram of a memory frame intermediate and a rearrangement buffer;

Figure 4 is a flow chart illustrating the operation of a transmitter and a receiver during a communication;

Figure 5 is a flow chart illustrating receiver operation during frame reception freshly transmitted;

Figure 6 is a flow chart illustrating receiver operation during frame reception retransmitted;

Figure 7 is a message diagram that illustrates the operation of the transmitter and receiver during a exemplary communication; Y

Figure 8 is a message diagram that illustrates the operation of the transmitter and receiver during a exemplary communication

Detailed description of the preferred embodiments

A procedure and apparatus is described for expand the range of sequence numbering for a protocol repetition of selective transmission. In the following description, the invention is presented in the context of a communication system personnel that work according to the use of processing techniques of CDMA signal of IS-707 e standards IS-95 Although the invention is especially suitable for use within such a communications system, It should be understood that the present invention can be used in other various types of communications systems that transmit data to through frames or packages, including both system wireless and network communication, as well as systems satellite based communication. In addition, throughout the application, it They expose several well-known systems in blocks. This is has done to avoid, unnecessarily, the description of the Invention be unclear.

Figure 2 is a block diagram of two communication systems configured according to an exemplary embodiment  of the invention. The highest transmission rate communication is driving from a transmitter 50 to a receiver 52. In a exemplary configuration, a transmitter 50 is located in a station 12 base and a receiver 52 is located in a wireless terminal 10, however, locations can be reversed. Inside of the transmitter 50, the control system 54 receives data frames from input / output (I / O) 56 and provides that data to the encoder 58. Encoder 58 performs a convolutional coding that generates code symbols that are received by modulator 60 digital. The digital modulator 60 performs a modulation of direct sequence over code symbols with one or more codes binary channel and one or more binary spreading codes that generate fragmented symbols in code elements that are received by radio frequency transmitter (RF) 62. The symbols fragmented code elements are converted in a way ascending to the carrier frequency band using the transmitter 62 RF and are transmitted from an antenna system 64 to through a diplexer 66.

Various procedures can be used and apparatus for performing digital modulation and conversion ascending RF in the present invention. A set of particularly useful procedures and apparatus are described in the US patent pending along with this 6,005,855 entitled "Method and Apparatus for providing Variable Rate Data In A Communications System Using Statistical Multiplexing "filed on April 28, 1995, the patent US 5,777,990 entitled "Method and Apparatus For Providing Variable Rate Data In A Communications Systems Using Non-Orthogonal Overflow Channels "presented on February 28, 1995, and US Patent 5,949814 "High Data Rate Supplemental Channel for CDMA Telecommunications System "filed on January 15, 1997, all of which have transferred to the assignee of the present invention. Should understood that some of the patent applications referred to previously they are focused on the direct link and, therefore, they are more suitable for use with the transmitter 50, while others are focused on the reverse link and therefore are more suitable for use with the receiver 52.

In an exemplary embodiment of the invention, the data transmitted from the antenna system 64 is formatted according to frame 70 that includes sequence field 72 (SEC number) of eight bits, relay flag 74, and field 76 of data. A frame 70 may include a CRC field 77 or other fields that are not shown because they are not particularly relevant in the present invention In a preferred embodiment of the invention, the frames are formatted substantially according to the structures of frame defined in the IS-707 standard, together with the relay indicator 74.

To provide data frames to the encoder 58 in an orderly manner, the control system 54 stores the frames within frame buffer 55 and updates a index value L_V (S). The frame buffer 55 and the index value L_V (S) are preferably stored inside of a memory system. In a preferred embodiment of the invention, the index value L_V (S) is a number of twelve-bit sequence that is incremented after the transmission of each plot, as described in more detail below. The eight least significant bits of index value L_V (S) are placed in the sequence field of a frame 72.

Within receiver 52, RF receiver 80 is converts down and digitizes the RF signals in which frame 70 is transmitted using the antenna system 82 and the diplexer 84. Digital demodulator 86 demodulates signals converted downwards, or "baseband", using the necessary binary codes that generate decision data from software received by the decoder 88. The decoder 88 performs Viterbi or reticular decoding of maximum probability which generates the hardware decision data 90 that is provided to controller 91.

Controller 91 reforms frame 70 using hardware decision data 90, and determines if the frame has been received in sequence, in relation to the frames that have already been received using the SEC number, the index variable L_V (N) and L_V (R) as well as the buffer 92 of reordering and NAK list 94, as described more fully detail below.

If controller 91 determines that the frame is has received out of sequence in relation to the frames that are already have received, or if the frame is received with error, generates a message of negative acknowledgment (NAK) that is received by the encoder 95. The encoder performs a convolutional coding, to generate code symbols that are a spread spectrum of direct sequence modulated by digital modulator 97, preferably according to the reverse link of IS-95, and fragmented symbols in code elements are converted from ascending form by the RF transmission system 98 and it transmit as the NAK 83 from the antenna system 82 through of diplexer 84. The L5_EQ for the frame with NAK is stored inside from list 94 of NAK.

Referring again to transmitter 50, RF receiver 67 receives the RF signal through system 64 antenna and diplexer 66. RF receiver 67 converts so descending and digitizes the RF signal generating samples that are demodulate using digital demodulator 68. The decoder 69 decode software decision data from the demodulator 68 digital and the control system 54 receives the decision data hardware from decoder 69, thereby detecting the NAK from the receiver 52 contained in the decision data of hardware.

The control system 54 receives the NAK 83 and retrieves the frame with NAK from the buffer memory of transmission. The recovered frames are retransmitted according to the original transmission as described above (including  the original sequence number).

Figure 3 is a diagram illustrating the configuration of frame buffer 55, memory 92 of reordering, and the indices L_V (S), L_V (N) and L_V (R), when used according to an embodiment of the invention.  Within the transmission buffer 55, the frames are already transmitted are shaded, and the frames to be transmitted They are not. In the preferred embodiment of the invention, the indexes L_V (S), L_V (N) and L_V (R) are numbers of twelve (12) bits The index L_V (S) is adjusted to the number of sequence of the next frame to be transmitted. When the frame is actually transmitted, the eight bit SEC number of the frame conforms to the eight least significant bits of the index L_V (S).

Within buffer 92 of reordering, the index L_V (R) conforms to the sequence of twelve bits of the next expected new frame. The index L_V (N) conforms to the 12-bit sequence of the frame Next necessary for sequential delivery, or for whose Processing is still pending. When a number has been sent NAK default without receiving the corresponding frame, the frame processing attempt is terminated and the data with the lost frame are passed to the upper layer protocols (by example, the transport layer). As shown, frames 96a - c with NAK can be received with sequence numbers between L_V (N) and (L_V (R) -1) MOD 4096, inclusive.

Figure 4 is a flow chart illustrating the operation of transmitter 50 and receiver 52 during a communication made according to an embodiment of the invention. The transmission starts at the transmitter in stage 100, and the reception at the receiver in step 101. In step 102, performs initialization, during which the index L_V (S) is set to zero inside transmitter 50 and L_V (R) is set to zero inside receiver 52.

In step 108, the transmitter transmits a frame (indicated by the dashed line) when the data is available for transmission, with the SEC number of the frame set to the least significant eight bits of the index L_V (S), referred to as V (S). Further, the retransmission indicator is set to zero to indicate that the plot is a newly transmitted plot. In step 112, the index L_V (S) MOD 4096 is increased, and in step 113 the transmitter Performs a receipt processing for any NAK message transmitted from receiver 52. In one embodiment of the invention, when data is not available, the frames "in wait "that have the current SEC number can be sent from Repeatedly until data is available (transmissions standby not shown).

In step 130, the transmitter determines whether a NAK has been received or is pending and, if so, frames with NAK are recovered from the transmission buffer using the long sequence number contained in the NAK message and retransmitted in step 132 with the original SEC number and the relay field set to one. Once the plot is retransmits, the pending or received NAK is purged and the processing then continue on stage 113.

If it has not been received or is not pending NAK message, the transmitter returns to step 108 and the Processing continues.

Within receiver 52, the processing starts at stage 101, and at stage 106 you receive L_V (S) from transmitter 50. In step 110, receiver 52 receives any frame transmitted from transmitter 50 on or else the stage 108 (new transmission), or in stage 132 (retransmission), and in step 114 examines the status of the indicator retransmission of the frame to determine if the received frame is a retransmitted frame or a new frame. If the plot is a plot retransmitted, the retransmission processing is performed in the step 116, and then the receiver returns to step 110. If the frame is not a retransmitted frame, the first processing frame transmission is performed in step 120, and then the step 110 is performed again.

Figure 5 is a flow chart illustrating operation of receiver 52 when processing the first transmission  of a frame during step 120 of Figure 4 according to a embodiment of the invention. First processing transmission starts at stage 150, and at stage 152 it adjusts L_SEC according to the following equation:

(1) L_SEC = {L_V (R) + [256 + SEC - V (R)] MOD 256} MOD 4096,

in which V (R) is the eight least significant bits of L_V (R) and SEC is the number of sequence contained in the SEC field of the frame that is processing In step 154 it is determined whether L_SEC is less than L_V (N) or that the frame has been stored in memory intermediate reordering. If so, the plot is discarded in the step 156, and the reception system returns from the processing of first transmission, in step 157. As indicated previously, L_V (N) is adjusted to the necessary frame following for sequential delivery of the data.

If L_SEC is not less than L_V (N) and the frame has not been stored in the reordering buffer, it is further determined, in step 158, if L_SEC is greater than or equal to L_V (N) and less than L_V (R), and if the frame has not been stored in the reordering buffer and, if so, the frame is discarded in step 156, and the reception system returns of the first transmission processing, at step 157. On the other mode, it is further determined, in step 160, if L_SEC is equal to L_V (R), and therefore is the next necessary frame for sequential delivery L_V (R).

If L_SEC is not equal to L_V (R), it has received a messy frame, and the frame is stored in memory  intermediate reordering in step 162 and L_V (R) is set to L_SEC in step 164. In step 166, the system of reception transmits one or more NAK messages requesting the retransmission of all frames not received from L_V (N) a (L_V (R) - 1) MOD 4096 inclusive. Receiving system then returns from the first transmission processing, in the step 176.

If, in step 160, it is determined that L_SEC is equal to L_V (R), the frame has been received in order, making which is also determined in step 170 if L_V (N) is equal to L_V (R), indicating that there are no frames with highlighted NAK. Yes L_V (N) is equal to L_V (R), L_N (N) and L_V (R) MOD 4096 are increased in step 172. The frame of data is delivered to the upper layer protocol in step 174 and the receiver returns from the first transmission processing, in the step 176.

If it is determined, in step 160, that L_V (N) is not equal to L_V (R), and therefore the frames with NAK remain highlighted, L_V (R) is increased MOD 4096 in stage 178, and in stage 180 the frame is stored in the buffer reordering. The receiver 52 then returns of the first frame transmission processing, at the stage 176.

Figure 6 is a flow chart illustrating operation of receiver 52 during step 116 when a Retransmitted frame is received according to an embodiment of the invention. Processing of the retransmitted frame begins at the stage 200, and in step 202 the SEC field in the received frame is used as the key to query an L_SEC associated with the SEC in the NAK list 94 (figure 2). In step 204 it is determined whether the L_SEC is less than L_V (N), or if the frame has already been stored in the reordering buffer and, if so, the plot is discards in step 206 and receiver 52 returns from processing of retransmission in step 208.

If L_SEC is not less than L_V (N) and the frame has not been stored in the reordering buffer, it is further determined, in step 210, if L_SEC is greater than or equal to L_V (N) and less than L_V (R) and if the frame has not been stored in the reordering buffer and, if so, the frame is stored in the reordering buffer in the step 212 before step 214. Otherwise, it is perform step 214.

In step 214, it is determined whether L_SEC is equal to L_V (N), and if not, the frame is discarded in step 216 since the retransmitted frame has a sequence number that is larger than the next expected new plot and therefore has An error occurred. Once the plot has been discarded, the receiver 52 returns from frame processing retransmitted in the step 208.

If L_SEC is equal to L_V (N), the data in all contiguous frames formed by adding the frame retransmitted that is being processed from L_V (N) onwards, they are delivered to the next higher processing layer in the step 218, and the frames delivered are removed from memory intermediate reordering in step 220. In step 222 L_V (N) conforms to LAST + 1 where LAST is the long number of sequence (L_SEC) of the last frame delivered to the upper layer in step 218. In step 224 the plot is removed from the list of NAK and receiver 52 returns to process the frame retransmitted in the step 226.

Figure 7 is a message diagram that illustrates the messages transmitted during an exemplary communication performed according to an embodiment of the invention. The transmitter 50 is shows on the left, and receiver 52 is shown on the right. The transmitter 50 maintains the L_V (S) index and the frames are transmit with value V (S) in the sequence field, in the that V (S) are the eight least significant bits of L_V (S). On receiver 52, the NAK list is displayed after each transmission. All numbers are shown in hexadecimal.

The first frame 230 is transmitted when the L_V (S) index is equal to 0x2FE, and therefore with a number of SEC of 0xFE. After transmission of frame 230, the L_V (S) index is increased to 0x2FF and frame 232 is transmitted with a SEC number of 0xFF. Both frames 230 and 232 are received with success for receiver 52, making the L_V (R) index Increase twice from 0x2FE to 0x300.

Frame 234 is transmitted with a SEC number 0x00 and not received successfully by receiver 52. L_V (S) it is then increased to 0x301 and frame 236 is transmitted with a SEC number of 0x01 and received successfully by receiver 52.

Upon receipt of frame 236, the receiver 52 detects the messy sequence number because the frame 234 was not received. In response, receiver 52 generates the message NAK 240 containing the twelve-bit L_V (R) index complete for the frame not received 0x300. In addition, receiver 52 update NAK list 94 to indicate that a NAK has been transmitted for a frame with the SEC number 0x00 and the number of L_SEC 0x300. Also, receiver 52 starts a NAK timer which tracks the time that has elapsed since the NAK message 240 transmission.

During the transmission of NAK message 240, transmitter 50 transmits another frame 238 with a SEC number of 0x02 that is successfully received by receiver 52. Upon receipt of message 240 of NAK, transmitter 50 generates frame 242 retransmitted that has the SEC number 0x00 and indicator 74 of retransmission (figure 2) set to one. Upon receipt of the frame 242 retransmitted, receiver 52 detects the bit of relay and map the SEC number with the SEC number in NAK list 94. Once the correspondence, the retransmitted frame 242 is placed within the buffer 92 reordering (from figure 2) and is deleted the entry in list 94 of NAK. Frames 244 and 246 are transmitted and then received in the normal way.

Figure 8 is an additional message diagram illustrating the operation of transmitter 50 and receiver 52, during a transmission in which the sequence number "is cyclically restarts ", when performed according to an embodiment of the invention. Frames 240a and 240b are transmitted with the numbers SEC 0xFE (all numbers are in hexadecimal) and 0xFF respectively, which correspond to values of 0x2FE and 0x2FF for the  L_V (S) index, and are successfully received by receiver 52, causing L_V (R) to be increased from 0x2FE to 0x300.

Frame 240c includes the SEC number 0x00 but it is not received successfully by receiver 52. Frame 240d includes the SEC number 0x01 and is properly received by receiver 52. Upon receipt of frame 240d, receiver 52 detects that the SEC number is greater than the eight least significant bits of L_V (R), and therefore that a frame has been received messy In response, receiver 52 updates L_V (R) to 0x302, which corresponds to the next expected frame, and places the SEC number of the frame not received in NAK list 94. In addition, the receiver 52 transmits the NAK 241 containing the number of L_SEC complete 0x300 of the frame that has not been received, and starts a timer that tracks the amount of time that has elapsed since the transmission of NAK 241. As shown in figure 8, however, NAK 241 is not received with success for transmitter 50.

The transmitter 50 continues to transmit frames as shown, including frames 240e - 240j, all which are successfully received by receiver 52. During the frame transmission 240e - 240j, the index L_V (S) it changes from 0x302 to 0x400, producing a cyclic reset in all eight less significant bits, and therefore in the SEC number content in the frames.

The 240k frame is transmitted with the SEC number 0x01 and is not received successfully by receiver 52. Frame 2401 is transmits with the SEC number 0x02 and is successfully received by the receiver 52. Upon receipt of frame 2401, receiver 52 detects a messy transmission, and responds by transmitting the NAK 243 containing the sequence value 0x401 and adding the number from sequence 0x401 to list 94 of NAK. Also, at this time Timer ends for NAK 241, making a second NAK 245 containing the sequence value 0x300 is transmitted to transmitter 50. Therefore, a second NAK is transmitted for the frame 240c In addition, receiver 52 sets L_V (R) to the number of next expected sequence 0x403. Note that the numbers of sequence transmitted in NAK 243 and 245 can be transmitted in a single message from NAK.

The transmitter 50 responds to NAK 243 and 245 transmitting the retransmitted frame 242a containing the data to from frame 240k, and frame 242b retransmitted containing data from frame 240c. Upon receipt of the plot 242a of retransmission, receiver 52 identifies the frame as a retransmitted frame, based on the status of indicator 74 of retransmission (figure 2). Once the plot is identified as a retransmitted frame, receiver 52 performs a query within from NAK list 94 using the SEC number and determine which frame It has been broadcast. The retransmitted frame 242a is then placed at the appropriate location within buffer 92 of reordering (figure 2), and the corresponding entry is removed from NAK list 94.

Upon receipt of frame 242b of retransmission, the receiver also identifies the type of frame and Make a query within the NAK list 94. When determines the identity of the plot, is placed inside the memory 92 intermediate reordering (figure 2), and input corresponding is removed from the NAK list 94. 50 transmitter then transmits the 240m frame that has the sequence number 0x03 that is successfully received by receiver 52. At this point, the NAK list 94 is empty.

As is evident from the transmission shown in figure 8, mark the frames as either new or Well retransmitted allows the receiver to process properly both the new and retransmitted frames that the same SEC numbers even when a cyclic restart occurs of the sequence number during a retransmission. This is due to that a frame retransmitted with the same SEC number as a frame  newly transmitted can be distinguished by the indicator of Relay Therefore, the present invention allows it to be process a larger number of frames using a sequence number of eight bits, and therefore supports data transmission rates significantly higher while maintaining a substantial compatibility with existing standards previously.

Therefore, a procedure and apparatus for expanding the sequence numbering range for a selective transmission repeat protocol. The description Prior to preferred embodiments is provided for allow any person skilled in the art to make or use the present invention The various modifications to these realizations will be readily apparent to experts in the technique, and the generic principles defined herein document can be applied to other embodiments without the use of the inventive faculty Therefore, the present invention does not have as aim to be limited to the embodiments shown herein document, but must be granted a scope according to the novel principles and characteristics as defined in the attached claims.

Claims (9)

1. A procedure to transmit data between a transmitter (50) and a receiver (52) using a frame (70) that it has a sequence number (72) and an indicator (74) of retransmission comprising the stages of:

to)

transmit the frame (70) a first time with said retransmission indicator (74) set to false and comprising the sequence number (72) a first number of bits and set to less significant bits of an index code comprising a second number of bits, greater in number than the first number,

b)

increase a value of said index code for the use of a following plot; Y

C)

retransmit the frame (70) a second time with said indicator (74) set to true if received in said transmitter (50) a negative acknowledgment message containing said frame index code (70).

2. The method according to claim 1, wherein said sequence number (72) comprises eight bits. 3. The method according to claim 1, which also includes the stages of:

quad

receive the plot (70);

quad

transmit said negative acknowledgment message when the frame (70) is received messy based on the number (72) of sequence.

4. The method according to claim 3, which also includes the stages of:

quad

maintain an index of L_V (R) of the frame expected next; Y

quad

maintain an index of L_V (N) of the frame Next necessary for sequential delivery.

5. The method according to claim 3, which also includes the step of maintaining an index value of L_V (S) of the next frame to be transmitted by first time. 6. A transmitter (50) to transmit data digital, comprising the transmitter (50):

quad

a control circuit (54) to generate, to individual data frames, respective sequence numbers, each comprising a first number of bits, deduced from of the least significant bits of an index code that it comprises a second number of bits, greater in number than the first number;

quad

a transmission circuit (62) to transmit each data frame with a respective sequence number and with a relay indicator as an encoded data frame over a carrier; Y

quad

a reception circuit (67) to receive and decode an encoded data frame comprising a code index and a negative acknowledgment message,

quad

and in which the control circuit (54) is willing to identify from the index code decoded a sequence number and a respective data frame for retransmission if said acknowledgment message is received negative that contains said index code, in which said relay indicator is set to true and said frame of encoded data is retransmitted by circuit (62) of transmission.

7. A receiver (52) to receive data digital, comprising the receiver (52):

quad

a reception circuit (80) to receive and decode an encoded data frame containing a field of data, and an associated sequence number comprising a first number of bits representing the least significant bits of a index code, and a retransmission indicator;

quad

a control circuit (91) to examine the status of the retransmission indicator and, if the retransmission indicator is set to true, said circuit is adapted control

to determine the index code from the sequence number received, index code comprising a second number of bits, greater in number than the first number,

to compare the determined index code with developed index codes for respective sequence numbers of received data frames above to identify the wrong messy reception of the encoded data frame received, and

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to generate the index code for transmission with an acknowledgment message negative receipt when this error is detected upon receipt of said encoded data frame; Y

quad

a transmitter (98) to jointly transmit the index code and the negative acknowledgment message as a data frame encoded on a carrier.

8. A system to transmit data through frames, comprising:

quad

a transmitter according to claim 6, which further comprises a transmission system (50) to transmit newly transmitted frames with a type field comprising said retransmission indicator set to newly transmitted and a sequence number, to maintain an index L_V (S) that increases after the transmission of each newly transmitted frame, and to transmit retransmitted frames in response to messages from acknowledgment of negative receipt; Y

quad

a reception system (52) for generating said negative acknowledgment messages when such frames just transmitted are received messy, to maintain a list of Negative acknowledgment messages to track of frames not received, and to reorder frames Retransmitted

9. The system according to claim 8, in the that said reception system is also to: keep a code of index L_V (R) indicating a next expected frame; receive newly transmitted frames that have a number of sequence; generate said negative acknowledgment message if said sequence number is greater than said expected frame next.